R库(RCurl)在travis-ci上的行为改变

Question

这段代码以前在travis-ci上工作但现在失败了.在appveyor上工作正常

RCurl::getURL( "ftp://ftp.cdc.gov/pub/data/yrbs/" , ftp.use.epsv = TRUE, dirlistonly = TRUE )

这是错误的文本 -

Error in function (type, msg, asError = TRUE)  : 
  server did not report OK, got 425
Calls: get_catalog ... <Anonymous> -> curlPerform -> .Call -> <Anonymous> -> fun

我认为我.travis.yml是一个非常标准的配置:

language: r
cache: packages
sudo: required
apt_packages:
- unixodbc-dev
- libarchive-dev

2018年2月底成功构建日志,网址为https://api.travis-ci.org/v3/job/343635739/log.txt

失败的构建日志2018年3月初https://api.travis-ci.org/v3/job/352115990/log.txt

libcurl块看起来几乎相同,但成功和失败之间有一个明显的区别 -

2月末成功:

2 upgraded, 35 newly installed, 1 to remove and 124 not upgraded.

3月中旬失败:

2 upgraded, 35 newly installed, 1 to remove and 135 not upgraded.

次要r会话信息更改:

2月下旬成功:

Session info ------------------------------------------------------------------
 date     2018-02-20                  
 DBI            0.7        2017-06-18 cran (@0.7)                       
 devtools       1.13.4     2017-11-09 CRAN (R 3.4.2)                    
 lodown         0.1.0      2018-02-20 Github (ajdamico/lodown@6a69363)  
 rlang          0.1.6      2017-12-21 cran (@0.1.6)                     
 srvyr          0.3.0      2018-01-24 cran (@0.3.0)                     

3月中旬失败:

 Session info ------------------------------------------------------------------
 date     2018-03-12                  
 DBI            0.8        2018-03-02 cran (@0.8)                       
 devtools       1.13.5     2018-02-18 CRAN (R 3.4.3)                    
 lodown         0.1.0      2018-03-12 Github (ajdamico/lodown@bef726b)  
 rlang          0.2.0      2018-02-20 cran (@0.2.0)                     
 srvyr          0.3.1      2018-03-10 cran (@0.3.1)